CN112881529B - Composite material structure damage monitoring method and system based on laser piezoelectric technology - Google Patents
Composite material structure damage monitoring method and system based on laser piezoelectric technology Download PDFInfo
- Publication number
- CN112881529B CN112881529B CN202110025861.5A CN202110025861A CN112881529B CN 112881529 B CN112881529 B CN 112881529B CN 202110025861 A CN202110025861 A CN 202110025861A CN 112881529 B CN112881529 B CN 112881529B
- Authority
- CN
- China
- Prior art keywords
- array
- scanning
- damage
- guide vector
- point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 62
- 238000012544 monitoring process Methods 0.000 title claims abstract description 56
- 238000000034 method Methods 0.000 title claims abstract description 40
- 238000005516 engineering process Methods 0.000 title claims abstract description 29
- 239000013598 vector Substances 0.000 claims abstract description 123
- 239000000463 material Substances 0.000 claims abstract description 25
- 238000012545 processing Methods 0.000 claims abstract description 10
- 235000019687 Lamb Nutrition 0.000 claims description 18
- 230000005284 excitation Effects 0.000 claims description 8
- 230000006870 function Effects 0.000 claims description 6
- 230000001960 triggered effect Effects 0.000 claims description 6
- 230000009131 signaling function Effects 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 abstract description 5
- 230000008569 process Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000003491 array Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000003331 infrared imaging Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/22—Details, e.g. general constructional or apparatus details
- G01N29/24—Probes
- G01N29/2418—Probes using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/18—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using ultrasonic, sonic, or infrasonic waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/02—Indexing codes associated with the analysed material
- G01N2291/028—Material parameters
- G01N2291/0289—Internal structure, e.g. defects, grain size, texture
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/04—Wave modes and trajectories
- G01N2291/042—Wave modes
- G01N2291/0427—Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- Pathology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Signal Processing (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Optics & Photonics (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The invention provides a composite material structure damage monitoring method based on a laser piezoelectric technology, which comprises the steps of receiving signals formed when a laser head scans all scanning points on a composite material plate globally every time; processing the signals received each time, acquiring the direct wave time delay from each array element to each scanning point, combining the direct wave time delay from the same scanning point to each array element, and calculating in a preset steering vector formula to obtain a steering vector array of each scanning point; and representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring the region between two scanning points with the minimum Euclidean distance calculation value, and further outputting the acquired region as a damage monitoring region. By implementing the method, damage monitoring and impact position estimation can be realized without measuring and calculating the material parameters of the material structure in advance.
Description
Technical Field
The invention relates to the technical field of composite material structure health monitoring, in particular to a composite material structure damage monitoring method and system based on a laser piezoelectric technology.
Background
Composite materials have light weight, high strength, and other desirable mechanical properties, and are widely used in industry. However, the composite material is prone to generate defects, reliability is reduced in the application process, the safety performance of the structure is threatened, meanwhile, the structural parameters of the industrially applied composite material are different, and the large complex structure can use the composite material with different material parameters to realize different functions of the structure. Therefore, for composite material structures with different material parameters, it is very important to monitor the damage.
In recent years, there have been many methods for damage monitoring of composite structures, and the use of various technologies has facilitated the development of structural monitoring techniques. The composite material structure with known material parameters can be conveniently simulated by using a finite element analysis technology, and in practice, the damage position can be estimated by adopting various effective damage monitoring technologies such as infrared imaging, acoustic emission, eddy current and the like in combination with a positioning algorithm.
However, for a composite material structure with unknown material parameters, an experiment for obtaining the material parameters needs to be performed first, and then the material parameters of the structure are obtained through calculation, so that the damage monitoring can be performed. Therefore, there is a need for an online monitoring method for damage to a composite material structure with unknown material parameters, which can achieve damage monitoring and impact location estimation without calculating the material parameters of the material structure in advance.
Disclosure of Invention
The technical problem to be solved by the embodiments of the present invention is to provide a method and a system for monitoring damage of a composite material structure based on a laser piezoelectric technology, which can realize damage monitoring and impact position estimation without calculating material parameters of the material structure in advance.
In order to solve the above technical problems, an embodiment of the present invention provides a method for monitoring damage to a composite material structure based on a laser piezoelectric technology, which is used for a composite material plate with unknown material parameters, wherein a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor are preset on the composite material plate, and the method includes the following steps:
s1, receiving signals formed by a laser head when all scanning points on the composite material plate are globally scanned every time; the laser head global scanning times correspond to the total number of array elements in the linear array piezoelectric sensor, and each global scanning of the laser head is triggered on the basis that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
s2, processing signals formed during global scanning of the laser head received each time to obtain the time delay of the direct wave from each array element to each scanning point, and calculating in a preset guide vector formula by combining the time delay of the direct wave from the same scanning point to each array element to obtain a guide vector array of each scanning point;
and S3, representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring the area between two scanning points with the minimum calculated Euclidean distance value, and further outputting the acquired area as a damage monitoring area.
Wherein the method further comprises:
collecting array signals of the damage points to be positioned to obtain the direct wave time delay from the damage points to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage points to be positioned, further comparing the guide vector array of the damage points to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point with the nearest distance from the damage points to be positioned as the position of the damage points to be positioned in the damage monitoring area.
The Lamb wave signal excitation of each array element is realized by using a function generator to call a 50KHz Lamb wave signal function and then using an amplifier to amplify the corresponding array element.
Wherein the preset guide vector formula is
Wherein,
a(θ i ) A guide vector of the ith scanning point; theta i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis, and N is the total number of scanning points;
and x k (k =1,2,. M) is the position of the kth array element, c is the speed of light, and M is the total number of array elements; tau is ki The time delay of the direct wave from the ith scanning point to the kth array element.
The embodiment of the invention also provides a composite material structure damage monitoring system based on the laser piezoelectric technology, which is used for a composite material plate with unknown material parameters, wherein the composite material plate is preset with a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor, and the system comprises:
the signal receiving unit is used for receiving signals formed by the laser head when the laser head globally scans all scanning points on the composite material plate every time; the laser head global scanning times correspond to the total number of array elements in the linear array piezoelectric sensor, and each global scanning of the laser head is triggered on the basis that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
the guide vector array obtaining unit is used for processing signals formed during the global scanning of the laser head received each time so as to obtain the time delay of the direct wave from each array element to each scanning point, and calculating in a preset guide vector formula by combining the time delay of the direct wave from the same scanning point to each array element to obtain a guide vector array of each scanning point;
and the damage monitoring area acquisition unit is used for representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring an area between two scanning points with the minimum calculated Euclidean distance value, and further outputting the acquired area as a damage monitoring area.
Wherein, still include:
and the damage point position estimation unit is used for acquiring an array signal of the damage point to be positioned so as to acquire the direct wave time delay from the damage point to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage point to be positioned, further comparing the guide vector array of the damage point to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point with the nearest distance from the damage point to be positioned as the position of the damage point to be positioned in the damage monitoring area.
Wherein the preset guide vector formula is
Wherein,
a(θ i ) A guide vector of the ith scanning point; theta i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis, and N is the total number of scanning points;
and x k (k =1,2,..., M) is the position of the kth array element, c is the speed of light, and M is the total number of array elements; tau is ki The time delay of the direct wave from the ith scanning point to the kth array element.
The embodiment of the invention has the following beneficial effects:
the method comprises the steps of obtaining Lamb wave propagation conditions in a composite material structure by utilizing a laser piezoelectric technology, obtaining a guide vector array of each scanning point to all array elements by using signals formed by a laser head when each array element is excited, representing differences according to Euclidean distance calculation values of the guide vector array, and estimating a damage monitoring area and an impact position, so that damage monitoring and impact position estimation can be realized without measuring and calculating material parameters of the material structure in advance.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is within the scope of the present invention for those skilled in the art to obtain other drawings based on the drawings without inventive exercise.
Fig. 1 is a flowchart of a method for monitoring damage to a composite structure based on a laser piezoelectric technique according to an embodiment of the present invention;
fig. 2 is a layout diagram of a laser experimental device for monitoring damage of a composite material structure in the composite material structure damage monitoring method based on the laser piezoelectric technology, which is provided by the embodiment of the invention;
fig. 3 is a schematic diagram illustrating non-difference time delay of a direct path between a scanning point and an array element in a composite material structure damage monitoring method based on a laser piezoelectric technology according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a composite material structural damage monitoring system based on a laser piezoelectric technology according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.
The inventor finds that when the composite material structure is excited by the piezoelectric sensor and laser propagates in a non-contact monitoring plate through Lamb waves, the waves are scattered when propagating to a damage position. Therefore, the damage position can be estimated by combining a positioning algorithm after signal characteristics are extracted through a signal processing technology according to Lamb wave scattering signals acquired by laser. Therefore, based on the theory, the inventor provides a composite material structure damage monitoring method based on the laser piezoelectric technology.
As shown in fig. 1, in an embodiment of the present invention, an inventor proposes a method for monitoring damage to a composite structure based on a laser piezoelectric technology, where the method is used for a composite material plate with unknown material parameters, and a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor are preset on the composite material plate, and the method specifically includes the following steps:
s1, receiving signals formed by a laser head when the laser head globally scans all scanning points on the composite material plate every time; the overall scanning frequency of the laser head corresponds to the total number of array elements in the linear array piezoelectric sensor, and each overall scanning of the laser head is triggered based on the condition that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
the specific process is that for a composite material plate with unknown parameters, an experimental device is built as shown in fig. 2, a line array sensor with M (for example, 7) array elements is arranged on the composite material plate, after a function generator calls a 50KHz Lamb wave signal function, each array element is respectively excited through amplification of an amplifier, each pair of array elements is excited, and a laser head scans all preset scanning points (N) once. Through M times of scanning, the global scanning information (containing N scanning point signals) obtained by different excitation array elements can be obtained.
S2, processing signals formed during global scanning of the laser head received each time to obtain the time delay of the direct wave from each array element to each scanning point, and calculating in a preset guide vector formula by combining the time delay of the direct wave from the same scanning point to each array element to obtain a guide vector array of each scanning point;
the specific process is that firstly, considering that the guide vector represents the information of the signal in the space, the guide vector comprises all the information of the signal space phase, and the time delay response is included. Since the time delay on the direct path does not vary (as shown in fig. 3) but the time delay for scattering of the signal (i.e., the damage location) varies, it can be considered that the time delay for the direct wave on the signal propagation path matches the information received by the conventional impact point excitation array sensor.
At this time, the signals formed during the global scanning of the laser head received each time are processed to obtain the time delay of the direct wave from each array element to each scanning point.
Secondly, for the steering vector, it can be expressed by equation (1):
a(ω 0 )＝exp(-jω 0 τ ki ) (1)
wherein k =1.. M; i =1.. N;
c is the speed of light and λ is the wavelength.
For linear arrays, the mutual delay expression between array elements is shown as formula (2):
in the formula, τ ki The time delay of the direct wave from the ith scanning point to the kth array element is obtained; x is the number of k (k＝1，2，...，M)x k (k =1,2,. And, M) is the position of the kth array element; the signal incidence parameter is assumed to be θ i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis (i.e., the angle to the line normal).
Therefore, the formula (1) can be transformed into a steering vector formula with respect to the azimuth angle θ based on the formula (2). As shown in equation (3):
wherein, a (θ) i ) Is the steering vector of the ith scanning point.
And (3) calculating the wavelength and the azimuth angle mathematically to obtain the guide vector of the corresponding scanning point. In the laser piezoelectric array method, because the time delay of the direct wave on the direct path has no difference characteristic, the time delay of the direct wave of each scanning point obtained by excitation on M array elements of the linear array can be used as tau in a guide vector ki And thus, a guide vector array in the laser piezoelectric array method is obtained.
Therefore, the time delay of the direct wave from the same scanning point to each array element is substituted into the guide vector formula (3) for calculation, and the guide vector array of each scanning point is obtained.
And S3, representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring the area between two scanning points with the minimum calculated Euclidean distance value, and further outputting the acquired area as a damage monitoring area.
The specific process is that after the guide vector array of all scanning points is obtained, because the guide vector is a quantity with an imaginary unit, the real part quantity of the imaginary unit of the guide vector is taken during the comparison processing. Thus, each scan point can be represented by the real unit in the steering vector for the excitation of the different array elements for that point, and because of the linear array, can be described as a column of vectors. By taking the Euclidean distance among the column vectors, the guiding vector difference information among different scanning points can be obtained, and according to the difference information, the array signal of the damage point to be positioned, which is acquired by the laser piezoelectric technology, can be monitored and the impact position can be estimated.
Therefore, the guide vectors in the guide vector array of each scanning point are all represented by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, the Euclidean distance between the columns of vectors is calculated, and further, the region between two scanning points with the minimum calculated Euclidean distance can be obtained and output as a damage monitoring region.
In the embodiment of the invention, the smaller the difference of the guide vectors is, the closer the real part unit characteristics of the guide vectors are, so that the possibility that the impact position of the damage point to be positioned is near the position of the scanning point is higher. Accordingly, the method further comprises:
collecting array signals of the damage points to be positioned to obtain the direct wave time delay from the damage points to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage points to be positioned, further comparing the guide vector array of the damage points to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point with the nearest distance from the damage points to be positioned as the position of the damage points to be positioned in the damage monitoring area.
Based on fig. 2 and fig. 3, an application scenario of the composite material structure damage monitoring method based on the laser piezoelectric technology provided in the embodiment of the present invention is further described:
taking a composite material structural plate with unknown material parameters as an example, the dimension is 300mm multiplied by 2mm, the layering information and the fiber direction are unknown, the composite material plate is clamped by a clamping device and is stably and vertically placed, a row of 7-array sensor arrays are pasted at the center of the composite material plate, a laser piezoelectric device is connected through a graph 2, a laser beam is vertically hit on the composite material plate, a series of operations such as adjusting the laser focal length, the distance and setting a reference point in a user interface are carried out, the composite material plate is slightly shifted, whether a signal image is generated on the laser piezoelectric user interface or not is observed, and the normal work of the laser piezoelectric device is ensured. The method mainly comprises the following steps:
(1) Piezoelectric excitation: after the laser related parameters are set, a 50KHz Lamb wave signal function is called in a function generator and is amplified by an amplifier to act on a piezoelectric sensor at the center of a material plate, and 7 sensors are sequentially and independently excited;
(2) Laser scanning: after the piezoelectric patch is excited, the laser beam starts to scan in order according to preset scanning points. The excitation of the different sensors needs to be rescanned once, so that the laser beam in this case is scanned 7 times in total;
(3) Acquiring a guide vector array: processing the signals scanned by the laser to obtain the time delay of the signals received by each sensor at the same spatial position, and substituting the time delay into a guide vector formula to obtain a guide vector array of each scanning point;
(4) Obtaining a damage monitoring area: the guide vector is an imaginary number with an imaginary part unit, the real part characteristics of all guide vectors are taken during processing, the guide vector of each scanning point can be represented by a vector described by the real part unit, guide vector difference information among different scanning points can be obtained by taking Euclidean distance among the vectors, the closer the real part unit characteristics of the guide vectors are when the difference is smaller, the higher the possibility that the impact position is near the position of the scanning point is, and the fault source signal acquired by the laser piezoelectric technology can be monitored and the impact position can be estimated according to the difference information.
As shown in fig. 4, a composite material structure damage monitoring system based on a laser piezoelectric technology provided in an embodiment of the present invention is used for a composite material plate with unknown material parameters, where a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor are preset on the composite material plate, and the monitoring system includes:
a signal receiving unit 110, configured to receive a signal formed when the laser head globally scans all scanning points on the composite material plate each time; the laser head global scanning times correspond to the total number of array elements in the linear array piezoelectric sensor, and each global scanning of the laser head is triggered on the basis that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
a guide vector array obtaining unit 120, configured to process a signal formed during global scanning of the laser head received each time, so as to obtain a direct wave time delay from each array element to each scanning point, and calculate in a preset guide vector formula by combining the direct wave time delays from the same scanning point to each array element, so as to obtain a guide vector array of each scanning point;
the damage monitoring area obtaining unit 130 is configured to represent the guide vectors in the guide vector array of each scanning point in real units, so that the guide vector array of each scanning point is a corresponding column of vectors, calculate an euclidean distance between the columns of vectors, obtain an area between two scanning points with a minimum calculated euclidean distance, and further output the obtained area as a damage monitoring area.
Wherein, still include:
and the damage point position estimation unit is used for acquiring an array signal of the damage point to be positioned so as to acquire the direct wave time delay from the damage point to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage point to be positioned, further comparing the guide vector array of the damage point to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point with the nearest distance from the damage point to be positioned as the position of the damage point to be positioned in the damage monitoring area.
Wherein the preset guide vector formula is
Wherein,
a(θ i ) A guide vector of the ith scanning point; theta i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis, and N is the total number of scanning points;
and x k (k =1,2,..., M) is the position of the kth array element, c is the speed of light, and M is the total number of array elements; tau is ki The time delay of the direct wave from the ith scanning point to the kth array element.
The embodiment of the invention has the following beneficial effects:
the method comprises the steps of obtaining Lamb wave propagation conditions in a composite material structure by utilizing a laser piezoelectric technology, obtaining a guide vector array of each scanning point to all array elements by using signals formed by a laser head when each array element is excited, representing differences according to Euclidean distance calculation values of the guide vector array, and estimating a damage monitoring area and an impact position, so that damage monitoring and impact position estimation can be realized without measuring and calculating material parameters of the material structure in advance.
It should be noted that, in the above system embodiment, each included unit is only divided according to functional logic, but is not limited to the above division as long as the corresponding function can be implemented; in addition, the specific names of the functional units are only for the convenience of distinguishing from each other, and are not used for limiting the protection scope of the present invention.
It will be understood by those skilled in the art that all or part of the steps in the method for implementing the above embodiments may be implemented by relevant hardware instructed by a program, and the program may be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (7)
1. A composite material structure damage monitoring method based on a laser piezoelectric technology is characterized in that the method is used for a composite material plate with unknown material parameters, a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor are preset on the composite material plate, and the method comprises the following steps:
s1, receiving signals formed by a laser head when the laser head globally scans all scanning points on the composite material plate every time; the laser head global scanning times correspond to the total number of array elements in the linear array piezoelectric sensor, and each global scanning of the laser head is triggered on the basis that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
s2, processing signals formed during global scanning of the laser head received each time to obtain the time delay of the direct wave from each array element to each scanning point, and calculating in a preset guide vector formula by combining the time delay of the direct wave from the same scanning point to each array element to obtain a guide vector array of each scanning point;
and S3, representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring the area between two scanning points with the minimum calculated Euclidean distance value, and further outputting the acquired area as a damage monitoring area.
2. A method for damage monitoring of a composite structure based on laser piezo technology according to claim 1, characterized in that the method further comprises:
collecting array signals of the damage points to be positioned to obtain the direct wave time delay from the damage points to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage points to be positioned, further comparing the guide vector array of the damage points to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point with the nearest distance from the damage points to be positioned as the position of the damage points to be positioned in the damage monitoring area.
3. The method for monitoring the structural damage of the composite material based on the laser piezoelectric technology as claimed in claim 1, wherein the Lamb wave signal excitation of each array element is realized by using a function generator to adjust a 50KHz Lamb wave signal function and then using an amplifier to amplify the corresponding array element.
4. The method for monitoring the structural damage of the composite material based on the laser piezoelectric technology as claimed in claim 1 or 2, wherein the preset guide vector formula is
Wherein, a (theta) i ) A guide vector of an ith scanning point; theta i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis, N is the total number of scanning points, and λ is the wavelength;
and x k (k =1,2.., M) is the position of the kth array element, c is the Lamb wave velocity, and M is the total number of array elements; tau is ki The time delay of the direct wave from the ith scanning point to the kth array element.
5. A composite material structure damage monitoring system based on laser piezoelectric technology is characterized in that the system is used for a composite material plate with unknown material parameters, a linear array piezoelectric sensor and a plurality of scanning points distributed around the linear array piezoelectric sensor are preset on the composite material plate, and the system comprises:
the signal receiving unit is used for receiving signals formed by the laser head when the laser head globally scans all scanning points on the composite material plate every time; the laser head global scanning times correspond to the total number of array elements in the linear array piezoelectric sensor, and each global scanning of the laser head is triggered on the basis that a corresponding array element in the linear array piezoelectric sensor is excited by a Lamb wave signal;
the guide vector array obtaining unit is used for processing signals formed during the global scanning of the laser head received each time so as to obtain the time delay of the direct wave from each array element to each scanning point, and calculating in a preset guide vector formula by combining the time delay of the direct wave from the same scanning point to each array element to obtain a guide vector array of each scanning point;
and the damage monitoring area acquisition unit is used for representing the guide vectors in the guide vector array of each scanning point by a real part unit, so that the guide vector array of each scanning point is a corresponding column of vectors, calculating the Euclidean distance between the columns of vectors, acquiring an area between two scanning points with the minimum calculated Euclidean distance value, and further outputting the acquired area as a damage monitoring area.
6. A composite structure damage monitoring system based on laser-piezo technology according to claim 5, further comprising:
and the damage point position estimation unit is used for acquiring array signals of the damage point to be positioned so as to acquire the time delay of direct waves from the damage point to be positioned to each array element, calculating in the preset guide vector formula to obtain a guide vector array of the damage point to be positioned, further comparing the guide vector array of the damage point to be positioned with the guide vector array of each scanning point, and determining the position of the scanning point, which is closest to the damage point to be positioned, as the position of the damage point to be positioned in the damage monitoring area.
7. A composite structure damage monitoring system based on laser-piezo technology according to claim 5 or 6, characterized in that the preset steering vectorIs given by the formula
Wherein, a (theta) i ) A guide vector of the ith scanning point; theta.theta. i (i =1,2.., N) is the azimuth angle of the ith scanning point, which represents the angle to the y-axis, N is the total number of scanning points, and λ is the wavelength;
and x k (k =1,2.., M) is the position of the kth array element, c is the Lamb wave velocity, and M is the total number of array elements; tau. ki The time delay of the direct wave from the ith scanning point to the kth array element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110025861.5A CN112881529B (en) | 2021-01-08 | 2021-01-08 | Composite material structure damage monitoring method and system based on laser piezoelectric technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110025861.5A CN112881529B (en) | 2021-01-08 | 2021-01-08 | Composite material structure damage monitoring method and system based on laser piezoelectric technology |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112881529A CN112881529A (en) | 2021-06-01 |
| CN112881529B true CN112881529B (en) | 2022-12-20 |
Family
ID=76047419
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110025861.5A Active CN112881529B (en) | 2021-01-08 | 2021-01-08 | Composite material structure damage monitoring method and system based on laser piezoelectric technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112881529B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113804765A (en) * | 2021-10-08 | 2021-12-17 | 金陵科技学院 | Method and system for positioning multiple damage areas of seal head part of pressure vessel |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535656A (en) * | 2014-12-17 | 2015-04-22 | 江苏大学 | All-optical non-contact type composite material plate layer crack damage detection system and method |
| CN109115894A (en) * | 2018-09-04 | 2019-01-01 | 温州大学激光与光电智能制造研究院 | A kind of composite panel damage detecting method based on Toeplitz approximation method |
| CN109374740A (en) * | 2018-09-21 | 2019-02-22 | 南京航空航天大学 | Synthetic aperture MUSIC damage positioning method based on array error correction |
| JP2019039902A (en) * | 2017-08-25 | 2019-03-14 | 株式会社東芝 | Linear scan ultrasonic flaw detector and linear scan ultrasonic flaw detection method |
| WO2019113994A1 (en) * | 2017-12-14 | 2019-06-20 | 南京航空航天大学 | Method for monitoring music corrosion based on excitation beam forming and weighted image fusion |
| WO2019201178A1 (en) * | 2018-04-17 | 2019-10-24 | 江苏必得科技股份有限公司 | Train component crack damage detection method and system based on lamb wave imaging |
-
2021
- 2021-01-08 CN CN202110025861.5A patent/CN112881529B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104535656A (en) * | 2014-12-17 | 2015-04-22 | 江苏大学 | All-optical non-contact type composite material plate layer crack damage detection system and method |
| JP2019039902A (en) * | 2017-08-25 | 2019-03-14 | 株式会社東芝 | Linear scan ultrasonic flaw detector and linear scan ultrasonic flaw detection method |
| WO2019113994A1 (en) * | 2017-12-14 | 2019-06-20 | 南京航空航天大学 | Method for monitoring music corrosion based on excitation beam forming and weighted image fusion |
| WO2019201178A1 (en) * | 2018-04-17 | 2019-10-24 | 江苏必得科技股份有限公司 | Train component crack damage detection method and system based on lamb wave imaging |
| CN109115894A (en) * | 2018-09-04 | 2019-01-01 | 温州大学激光与光电智能制造研究院 | A kind of composite panel damage detecting method based on Toeplitz approximation method |
| CN109374740A (en) * | 2018-09-21 | 2019-02-22 | 南京航空航天大学 | Synthetic aperture MUSIC damage positioning method based on array error correction |
Non-Patent Citations (2)
| Title |
|---|
| Phase correction improved multiple signal classification for impact source localization under varying temperature conditions;Zhenghao Zhang 等;《Measurement》;20191213;第152卷;第1-8页 * |
| 基于阵列传感器的复合材料结构损伤MUSIC成像方法;鲍峤 等;《复合材料学报》;20170228;第34卷(第2期);第456-462页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112881529A (en) | 2021-06-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| RU2019104572A (en) | LASER ULTRASONIC SCANNING FOR VISUALIZATION OF DAMAGE OR IMPACT | |
| CA1087725A (en) | Piezoelectric acoustic emission instrumentation | |
| US7855368B2 (en) | Air-coupled acoustic thermography for in-situ evaluation | |
| JP5397451B2 (en) | Tissue material measurement system | |
| US20050217381A1 (en) | Thermal-acoustic scanning systems and methods | |
| CN112881529B (en) | Composite material structure damage monitoring method and system based on laser piezoelectric technology | |
| US20080314153A1 (en) | Hand-held flaw detector imaging apparatus | |
| Yuan et al. | Neural network method based on a new damage signature for structural health monitoring | |
| Ernst et al. | Acoustic emission localization in beams based on time reversed dispersion | |
| WO2017041668A1 (en) | Doppler imaging method and apparatus | |
| Sohn | Reference-free crack detection under varying temperature | |
| Bastani et al. | Identification of temperature variation and vibration disturbance in impedance-based structural health monitoring using piezoelectric sensor array method | |
| KR101242888B1 (en) | Measuring Method and Measruting Apparatus of Poisson's Ratio | |
| Michaels et al. | Damage detection in plate structures using sparse ultrasonic transducer arrays and acoustic wavefield imaging | |
| JP4795925B2 (en) | Ultrasonic thickness measurement method and apparatus | |
| Clark et al. | Spatially resolved acoustic spectroscopy (SRAS) microstructural imaging | |
| US10883969B2 (en) | System and method for inspecting a structure with coda acoustic waves | |
| Yan et al. | Quantitative structural damage detection using high‐frequency piezoelectric signatures via the reverberation matrix method | |
| US11796511B1 (en) | Structural monitoring system | |
| US20220128353A1 (en) | Structural Health Monitoring Method and System | |
| JP2006313115A (en) | Ultrasonic flaw detecting method and ultrasonic flaw detector | |
| KR102112032B1 (en) | Method of inspecting structure and inspection system | |
| RU2372615C1 (en) | Method of detecting acoustic emission signals in metals | |
| JPH076956B2 (en) | Method for measuring dynamic response characteristics of AE sensor | |
| Imano | Detection of drilled hole on subsurface of aluminum plate with rayleigh ultrasonic wave field by laser probing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |